1. Field of the Invention
The invention is directed to the field of installing wiring devices to ganged boxes mounted in building walls and more particularly to the provision of cover plate devices which can be used to cover such wiring devices to prevent unwanted access to such wiring devices and at the same time provide a finished look without exposed fasteners.
2. Description of the Prior Art:
At present when it is desired to install a wiring device such as a switch, a receptacle, a duplex receptacle, a combination receptacle and switch, etch, in a wall of a building, whether public, commercial or residential, it is necessary to cut a hole into such wall and install a ganged box adjacent the hole by attaching such box to a stud or the like. The ganged box is hollow to receive such wiring devices and provides pairs of mounting ears for mounting the wiring devices within and to the box. The size of the box is selected to accept all the wiring devices required at that location and the number of pairs of mounting ears will be equal to the number of possible wiring devices which the box can receive. Once the wiring device is connected to the various conductors it will service, the wiring device is screwed to at least one pair of ears to mount the wiring device in and to the box. When all wiring devices are in place a cover plate having suitable apertures through it will be installed over the exposed wiring devices and the ganged box. The method of fastening the cover plate to the wiring devices is to use screws which pass through the cover plate and are received in threaded apertures in such wiring devices. The usual arrangement of mounting screws is one between each duplex receptacle and two, one to each side, for a switch. Thus, when a prior art wiring system containing two duplex receptacles and a switch was completes one could see four exposed mounting screws. This made the completed job unsightly and could expose the user to a shock hazard if the correct insulation were not used during assembly.
One prior art approach to hide these unsightly and potentially hazardous fasteners is shown in U.S. Pat. No. 4,873,396 issued Oct. 10, 1988 to Guity-Mehr. The cover plate was fashioned with an M-shaped groove near the bottom of the plate's back surface which could be positioned under the head of the lower fastening screw used to anchor the wiring device to the ganged box mounting ear. This mounting screw would have to be mounted so that the proper length of its body remained outside of the wiring device to be gripped by the M-shaped groove. If the screw was not sufficiently installed the cover plate would be free to rattle and if the screw was installed too deeply the M-shape groove could not be positioned under the screw head.
Once the cover plate was positioned with the M-groove under the mounting screw, the cover plate is positioned so that the second mounting screw can be installed in a recessed groove in the front of the cover plate and screwed into the wiring device. Then a screw groove cover is fitted over the screw groove to hide the screw head and the screw groove.